Monitoring the vital signs of a patient is important for the management of patients who are in need of frequent routine care. This care may include transporting patients from one location to another within the hospital. The monitoring of vital signs is also important to doctors who practice family medicine, as well as to surgical and nonsurgical specialists, in such fields as otolaryngology, cardiology, and gastroenterology, to name a few.
More and more medical and surgical treatments are being carried out on an outpatient basis and, in many instances, doctors are performing these procedures on patients who, because of their medical history, stand a chance of developing hypertension or hypotension, apnea, bradycardia or tachycardia during the course of the treatment.
Presently available automatic blood pressure, pulse and respiration rate monitors are usually cumbersome, immobile, and very expensive. These monitors are usually permanently located on shelves or in wall units in the ICU of the hospital. The alternatives to these monitors, such as pulse measurement by palpation and blood pressure measurement by aneroid or mercury-filled sphygmomanometers with a manually inflated cuff, are inconvenient. Other monitors, such as portable digital blood pressure and digital pulse measuring devices which are available as home electronic items, are not sufficiently durable to be used in a physician's office or in a hospital.
Rapid and continuous vital sign retrieval is often necessary outside the ICU/CCU setting, especially in those areas where patients receive outpatient surgical and semi-surgical procedures. This applies particularly to those patients at high risk of cardiovascular complications due to preexisting disease and ongoing drug therapy. Present practice outside the ICU/CCU setting involves the use of a blood pressure cuff and mercury filled sphygmomanometer or aneroid sphygmomanometer with auscultation through a stethoscope for Korotkoff sounds, manual timing of pulse rate and manual inflation of a blood pressure cuff.
The areas in medicine where the need exists for compact, inexpensive and versatile vital sign measuring and display units include GI endoscopic surgery, cardiology stress testing, pulmonary medicine, ER/ICU/CCU, intermediate care unit settings for the "not too ill", ENT, dentistry, and oral surgery. In these areas, vital sign measurements such as blood pressure, pulse, temperature and respiratory rate (apnea) are continuously required. Continuous vital sign monitoring particularly applies to patients with significant cardiovascular disease where rapid and accurate assessment of the vital signs of a patient is required.
GI medicine often entails invasive high risk situations such as the evaluation of massive gastrointestinal bleeders, with serious underlying chronic illness such as arteriosclerotic heart disease or chronic obstructive pulmonary disease. Patients are also put at risk while undergoing modern endoscopic therapeutic procedures with esophageal scleroinjection of varices, colonoscopic polypectomy, laser control of bleeding peptic ulcers, sphincterotomy, and balloon dilatation of the lower esophageal, pyloric or oddisphincter. Often a nurse assistant, alone with a patient, has to provide the appropriate dose of drugs, provide the correct accessories, and be certain of the hemodynamics of patients who quite often are old, infirm and sensitive to both sedatives and narcotic analgesics. These situations provide a setting where the treating physician or nurse would require a continuous monitoring of the vital signs of a patient.